Oxygen-18 (18 O, Ω [1]) is a natural, stable isotope of oxygen and one of the environmental isotopes. 18 O is an important precursor for the production of fluorodeoxyglucose (FDG) used in positron emission tomography (PET). Generally, in the …

In geochemistry, paleoclimatology and paleoceanography δ18O or delta-O-18 is a measure of the deviation in ratio of stable isotopes oxygen-18 (18 O) and oxygen-16 (16 O).

Oxygen-18 is a stable isotope of the chemical element oxygen, which has 10 neutrons in its atomic nucleus in addition to the element-specific 8 protons; the sum of the number of these atomic nucleus building blocks results in a mass number of 18.

Oxygen-16 is the dominant isotope, making up more than 99 percent of all natural oxygen; oxygen-18 makes up 0.2 percent. However, the exact concentration of oxygen-18 in precipitation, particularly at high latitudes, depends on the temperature.

Late in a massive star's life, 16 O concentrates in the Ne-shell, 17 O in the H-shell and 18 O in the He-shell. Natural oxygen is made of three stable isotopes, 16 O , 17 O , and 18 O , with 16 O being the most abundant (99.762% natural abundance).

“Light” oxygen-16, with 8 protons and 8 neutrons, is the most common isotope found in nature, followed by much lesser amounts of “heavy” oxygen-18, with 8 protons and 10 neutrons. The …

Use of the compounds, “labeled” Oxygen-18 isotope, allows identifying causes of many diseases of the nervous and cardiovascular systems, to diagnose lung diseases and determine the effectiveness of pharmaceuticals in the study and treatment of brain diseases.

Oxygen-18 (18 O, Ω [1]) is a natural, stable isotope of oxygen and one of the environmental isotopes.

It is called "light" because a small fraction of oxygen atoms have 2 extra neutrons and a resulting atomic weight of 18 (18 O), which is then known as "heavy" oxygen. 18 O is a rare form and is found in only about 1 in 500 atoms of oxygen.

Isotopes of elements are designated by their mass number. Oxygen atoms with a mass number of 16 are called oxygen-16, or O-16, while oxygen atoms with a mass number of 17 are called oxygen-17, or O-17, and oxygen atoms with a mass number of 18 are called oxygen-18, or O-18.